This invention relates to a system controlling communication between electronic devices.
In some cases, separate electronic control devices including microcomputers are connected via a common data link to provide communication therebetween. For example, in some modern automotive vehicles, separate microcomputer-based control devices such as an engine control unit, a transmission control unit, and a shock absorber control unit, are connected via a common data link to communicate with each other. In such an automotive communication system, sensors detecting control parameters are generally connected to nearest control units, respectively. Control data signal derived through the sensors are transmitted between the control units via the common data link.
In automotive cases, sensors generating signals desired to undergo quick transmissions and sensors generating essential signals are directly connected to associated control units via additional exclusive lines, respectively. If these direct connections via the exclusive lines fail, a serious problem can arise.